66776704 has 16 divisors (see below), whose sum is σ = 133031970. Its totient is φ = 33388288.

The previous prime is 66776693. The next prime is 66776713. The reversal of 66776704 is 40767766.

It can be written as a sum of positive squares in only one way, i.e., 63361600 + 3415104 = 7960^2 + 1848^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260719 + ... + 260974.

Almost surely, 2^66776704 is an apocalyptic number.

66776704 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

66776704 is a deficient number, since it is larger than the sum of its proper divisors (66255266).

66776704 is an equidigital number, since it uses as much as digits as its factorization.

66776704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 521707 (or 521695 counting only the distinct ones).

The product of its (nonzero) digits is 296352, while the sum is 43.

The square root of 66776704 is about 8171.7014140263. The cubic root of 66776704 is about 405.7031001724.

The spelling of 66776704 in words is "sixty-six million, seven hundred seventy-six thousand, seven hundred four".